The invention relates to a brazed plate heat exchanger with a stack of heat exchanger plates and at least one functional component physically connected by means of piping and in terms of flow to the stack, like a collecting tank.
The invention also concerns a method for production of such brazed products.
These brazed products, which are made available to automobile manufacturers as a component of air conditioning systems, are being increasingly proposed of late.
The following examples can be mentioned: KR 10 2011 002 139 A, WO2009/065812 A1, FR 2 947 041 A1, FR 2 947 045 A1, EP 2 420 763 A2 and DE 10 2011 007 701 A1.
The plate heat exchanger in the aforementioned examples is a condenser in which a refrigerant is condensed by means of a liquid coolant and temporarily stored in the collecting tank in order to ensure separation of the liquid phase from the gas phase of the refrigerant. The piping serves to direct the refrigerant, which has at least partially flowed through the plate heat exchanger, into the collecting tank and/or from it. In many cases the condenser has a condensation part, say, a separate plate stack or a plate stack section that is intended for condensation of the refrigerant, and a supercooling part, which can be a corresponding different plate stack section or another separate plate stack provided for further supercooling of the refrigerant. The collecting tank can be situated between the condensation part and the supercooling part or also (viewed in terms of flow) after the supercooling part.
The prior art just sketched has already been essentially described previously per se, namely on pages 3, 5 and 7 of DE 19 881 14 T5. The collecting tank is referred to there as a coolant tank integrated in the condenser.
In the references of the prior art the applicants dealt more with variants of physical embodiments of the products than with the question as to how such brazed products can be produced cost-effectively.
However, it was discussed in the aforementioned EP document, paragraph 0016, that the product referred to as a condenser module there is produced in a brazing furnace with a single brazing process. In this reference the condensation part and the supercooling part are situated on a common base plate. The condensation part and the corresponding plates stack extend upward from the top of the base plate and the plate stack of the supercooling part is situated on the bottom of the base plate. The collecting tank stands on a lateral protrusion of the base plate. It is releasably or unreleasably fastened there. According to this reference the piping referred to there as a transfer tube must be subsequently screwed or welded on (paragraph 0021) in order to complete the already brazed condenser module.